Pump for refrigeration systems



Nov. 26, 1929. Y J. 6. KING 1,736,973

- PUMP FOR REFRIGERATION SYSTEMS Filed Jui 1 s Sheets-Sheet 1 MZHEESES fz'zuenZar Nov. 26, 1929. v J. G. KING 1,736,973

PUMP FOR REFRIGERATION SYSTEMS Filed July 1 2 s Sheets-Sheet 2 Nov. 26, 1929. J. G. KING 1,736,973

PUMP FOR REFRIGERATION SYSTEMS Filed July 19. 1920 5 Sheets-Sheet 3 [UL/EHZ'F W Patented Nov. 26, 1929" UNITED STATES PATENT OFFICE JESSE G. KING, OF DAYTON, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TO GENERAL IOTORS RESEARCH CORPORATION, OF WARE DAYTON, OHIO, A CORPORATION OF DELA- PUMP FOR REFRIGERATION SYSTEMS Application filed July 18, 1920. Serial No. 397,519.

in which the driving and driven elements are completely sealed'from each other by a fluidtight partition. More specifically it is'an object of the invention to provide an improved power transmitting device in which the elements are sealed from each other by a flexi bl'e metal partition.-

Another object of the invention is to so arendurance or long life. j

Another object is to so arrange the partition that it will be subjected to the minimum stress under operating conditions.

Further objects and advantages of the present invention will be apparent from the folrange such a partition that it will have great lowing description, reference being had to the accompanying drawings, wherein a preferred embodiment of the inventionis clearly shown.

In the drawings:

Figxl is a vertical longitudinal section of the compressor showing certain portions in elevation.

Fig. 2 is a similar view with the section taken at right anglesto that of Fig. 1.

Fig. 3 is a diagrammatic representation of a refrigeration system showing the compressor or pump somewhat enlarged with respect to the remainder of the system, and showing its relation thereto.

' Figs. 4, 5, 6, 7 and 8 illustrate certain details of the apparatus.

The known refrigeration'systems comprise a compressor to compress the refrigerant gas; a condenser for cooling and condensing to a liquid the compressed gas, and an expansion chamber wherein the liquefied refrigerant is allowed to expand and in theexpansion absorb heat from the atmosphere or other medium surrounding the chamber. The usual expansion chamber is in the form of a coil submerged in a tank of brine, the expansion of the gas abstracting heat from the brine and chilling it to the desired low temperature.

In the known systems, difliculty has been experienced in preventing leakage of the refrigerant from the apparatus and attempts have been made to reduce or overcome this leakage. If the compressor is not enclosed but is provided merely with an inlet and an outlet for gas, leakage may occur around the piston or at other places. If the compressor is enclosed in a chamber and driven by means of a shaft through the wall of the chamber,

there is necessitated a packing gland for the shaft. This construction is found in a num- "ber of refrigerating systems but it doesnot eliminate entirely leakage of gas or oil and produces considerable friction, thus causing a waste of power. j

In the construction shown in the drawings,

the compressor is enclosed in a. chamber and driven by a motor or other source of power positioned outside of the chamber, but the packing gland has been eliminated and there has been substituted in its place anefi'ective seal for the chamber, thus preventing leakage of either refrigerant or oil. from the system or air into the system.

In the construction shown in the drawings, Y

which construction is a preferred embodiment of the inventlon, the pump comprises a housing 10 which: is adapted to enclose the pump cylinders and pistons. In the form shown, the housing is provided with a base portion 10 and two opposite and aligned cylinders 11 in its upper portion. Extending laterally from the cylinders and suitably secured to the base portion 10' is a crank case portion 10* adapted to receive the driving mechanism hereinafter'to be described.

Operating within the cylinders 11 are pistons 12, and these pistons are shown as carried upon the two ends of a single piston rod 13.

The pistons 12 may be of any suitable or desired form, but the form indicated in the drawings, has been found to be satisfactory and to give excellent results and is the form piston rod longitudinally within the piston 1 member 20. This piston rod is provided with a longitudinal opening 23 extending from near its central portion to within a short distance of its end. At a suitable point near the ends of the piston rod lateral openings extend from the passage 23 into an annular I space 24 within the piston member 20. The

piston rod is also provided at its end with .the valve surface 25 coacting with the valve seat 21 within the end of piston member 20. The annular space 24 above referred to, is in direct communication with this valve formed in the end of the piston.

This form of piston provides a positively actuated inlet valve as well as a suitable form of compressor piston.

The piston rod 13 may be reciprocated by any suitable driven member having a power transmitting connection with a driving member outside of the housing 10. I prefer to operate the piston rod by means of a driven member partaking simultaneously of motion in different directions, one of which may take place principally inside of the housing 10 and the other of which may take place principally outside of the housing 10. These different mot-ions may for example, be simple planar oscillation slmultaneously in opposite directions as illustrated in Fig. 1.

In the present modification piston rod 13 carrying the pistons 12 is actuated by means of a driven member in the form of a pivoted lever designated as a whole by the numeral 40. This lever is pivoted at a point intermediate its ends, the end opposite the pump being adapted to be oscillated by means of a crank connected to a suitable driving means.

The central portion of the piston rod 1s provided with a slot 26, and passing through the rod and the slot is a pin 27 upon which is journaled a block 28 having flat bearing surfaces for a fork 29 formed on the actuating lever or walking beam 40.

In the form illustrated, the lever 40 is provided with outwardly and downwardly extending arms 41 provided at their lower ends upon suitable spinthe housing. At a point immediately below the junction of the arms 41 with the mam or body portion of lever 40, this body portion of lever 40 is provided with a disc portion 45 having upon its under side an annular groove 46, the purpose of which disc and groove will be explained later. The lower main portion of the lever is screw-threaded and carries a fork member 43 fastened thereto by means of a nut 44. This fork member 43 has its upper portion in the form of a sleeve fitting over the lower portion of the lever 40. This fork 43 coacts with a driving member in the form of a crank 50, a suitable ball-bearing 51 being provided to reduce friction.

ings carried by the base for the housing and is the continuation of a shaft 52 upon which is mounted the gear 53 indicated in the drawings as being driven by another gear 54 which is in its turn driven by a motor indicated by the dotted line 55'.

The housing 10 is separated fromthe crank case portion 10 containing the gearing and crank 50 by means of a plate provided at its central portion with an opening through The crank 50 is journalled in suitable bear-- which extends the lever 40. This opening designated by the numeral 61 is sealed against leakage of the refrigerant from the housing 10 to the opening 61, by means of a flexible sleeveor diaphragm 62, preferably in the form of an elastic metal bellows such as is commonly known in the trade under the name of sylphon, which sleeve is sealed, as by brazing, or otherwise secured to the plate 60 around the opening 61 and is at its upper end sealed by brazing or otherwise secured to a flat ring 63. This ring 63 is held tightly against disc or boss 45 on lever 40 by the upper end of forked member 43 which is in turn held tightly upon lever 40 by the nut 44. A suitable gasket 65 in groove 46 is provided in order to make a gas-tight closure of the upper end of the flexible sleeve 62, and likewise, a suitable gasket is provided between the plate 60 and the housing 10, as shown, to make a gas-tight connection between them. The plate 60 and flexible sleeve or bellows 62 are so located longitudinally of the lever 40 that the axis-of oscillation .of the lever 40 (determined by the pivots 42) will pass sleeve between the ends of the sleeve 62 and preferably at the point midway between the normal positions of the end planes of the sleeve. The word normal here refers to the positions of these elements of the .bellows when the bellows is free and at rest. The purpose of this location is to permit the flexing of the sleeve in its natural manner and to reduce to a minimum the stresses set up during flexing, as explained below. I

Fig. 5 illustrates the natural flexing of the bellows from which the location of the pivot axis 42 of the driving shaft is determined. In order to increase the life of the bellows under repeated flexing, and to decrease the resistance offered by the bellows to such flexing and thus decrease the amount of power remsaovs quired to drive the apparatus, it is desirable to eliminate side stresses on the bellows and to subject the bellows to the minimum stress for a given displacement or amount of flexing. That is, when the bellows is flexed, all forces transmitted from one corrugation to the next should act in lines which'are as nearly as possible perpendicular to the planes of the corrugations and should not have any component in a direction parallel to such planes. And moreover such forces between any pair of corrugations should be a minimum for a given flexure of the bellows. If such a bellows is supported with one end fixed and with its axis in a vertical line and the other end of the bellows is free, the bellows will oscillate or vibrate freely when the free end has been subjected to abending force applied at a.

single point and the force has been suddenly removed. During this 'free vibration the bellows flexes in its natural manner and it will be evidentthat in such flexing the bending stresses set up in the bellows at any given point will be a minimum for a given amount of fiexure. In flexing naturally the bellows takes a form illustrated in Fig. 5 in which the normal axis ab always assumes the form of a simple curve ab which I believe to be a circular are normal to the end planes of the bellows. And I believe that the free end 0d of the bellows always remains tangent to a sphere whose center is the point elocated on the line a?) midway between the no mal positions of the end planes.

Accordingly I construct and arrange the bellows and the pivoted lever 40 so that during movement of the lever the bellows isconstrained to flex in its natural manner, that is to say the plancof the free end ofthe bellows is maintained tangent to a sphere whose center is the point 0. This is accomplished by 10- eating the point of change of motion (that is, the pivot) of the member 40 at the point 6.

Thus in Fig. 5 the lines ac and eb represent the axes perpendicular to the endv planes of the bellows and these lines always intersect at apoint on the normal axis of the bellows midway between the normal positions of the end planes. The line eb also represents the axis of the portion of the lever 40above the pivot 42. Thus during movement of the driving and driven members the bellows is flexed so as to oscillate between two positions on either side of its normal axis. In the case illustrated this oscillation is simple planar oscillation while in the embodiment of the invention shown in my application Serial No. 400,894 a portion of the bellows nutates, the point e being referred to as the center of oscillation (or more specifically in cases where the bellows nutates, as the center of nutation) As indicated in the drawings, particularly in Figs. 5 and 6, the preferred form of sleeve used for this purpose is a corrugated metallic sleeve known in trade as a sylphon. Such a through outlet 72 and and such driving means will form of sleeve is well known and forms the subject of various patents already granted. This form of sleeve has been found to give satisfactory results, permitting the rapid actuation of the pump, forming an efiective seal for the chamber or housing containing the pump, and offering only a very small resistance to the oscillation of lever 40 upon its pivots 42.

' The pump and housing will of course be provided with suitable inlets and outlets for fluid, such an inlet being indicated at'70, Fig.

2, and an outlet being indicated at 72, Fig. 1. The outlets, 1n the formshown, lead from small valve chambers 73 containing the stems cuit is provided for the refrigerant, which circuit presents no opportunity for leakage.

The refrigerant will pass from the compressor P, through conduit P, into condenser C, then through conduit G into the expan- ;sion chamber or coil indicated-as enclosed within abrine tank designated E. From the latter, the expanded refrigerant will be drawn by compressor P through conduit E, again compressed and returned to the system. Suitable valves and control apparatus, not forming a part of the present application will of course be provided.

The path of the gas through the compressor 1s, asmay readily be seen, into thehousing 10 through-inlet 70, thence to the slotted portion of the piston rod 13, then through passage 23, chamber 24, and .valve 21, to the cylinder 11. Upon compression, the gas then "passes through valve 71 into chamber 73 and thence to the condenser. The portion of the housing 10- in direct communication with the inlet may be termed the low-pressure chamber, while the conduit P and chamber 73 in direct communication therewith may be termed the high-pressure chamber.

.It will be readily noted that by the use of a seal for the housing 10 enclosing the pump, a refrigeration system which is entirely sealed against leakage of refrigerant or oil from the system or air into the system, is provided.

While the description has indicated the gearing connected to a motor, it will'be read ily understood that any suitable form of driving means may-be used to actuate the pump, 7 be designated in the claims by the expression source of, power or primemover.

Further, while the specific description has said bellows.

a bellows surroun been confined to a pump for refrigeration apparatus, it will be readily understood that this form of pump may be found suitable for other forms of apparatus, and the invention should not be limited to this art.

Again, while the form of mechanism herein shown and described, constitutes preferred embodiment of one form of the invention, it will be understood that other forms might be adopted and various changes and alterations made in the shape, size, and proportion of the elements therein without departing from the spirit and scope of the invention.

What is claimed is as follows:

1. A compressor having a casing, a walking beam disposed within said casing, a bellows surrounding said beam near the center thereof, one end of the said bellows being hermetically sealed to the casing and the opposite end being similarly sealed to the sa d walking beam, a member extending outward from the said walking beam where said bellows is sealed thereto, arms extending laterally from said member toward the longitudinal center of said bellows and bearings for said arms at the approximate longitudinal center of said bellows,

2. A compressor having ing beam disposed within said casing, a bellows surrounding said beam near the center thereof, one end of the said bellows being hermetically sealed to thecasing and the opa casing, a walkposite end being similarly sealed to the said" fulcrum for said beam' walking beam, and a at the approximate longitudinal center of the 3. Arefrigerant compressor comprising a pump "hamber, a cylinder and piston associated therewith, a power train, a walking beam connecting the power train and piston,

' a gas-tight bellows connected at one. end so as to cover the pump chamber and at the other end connected to the walking beam, and a trunnion support for said walking beam outside the bellows, the axis of said support being within the length of the bellows,

4. A refrigerant compressor comprising, a power train casing and 'a compressor casing, a walking beam extending from one casing into the other, a flexible gas-tight bellows with its ends connected to the walking beam and casingto form a. gas-tight closure between the walking beam and compressor casing, a trunnion yoke carried by the walking beam with its axis within the length of the bellows and outside of the bellows, and support for said trunnion yoke.

5. A compressor casing, a cylinder having a piston therein mounted on the casing, a crank case extending laterally from said casing, a walking beam disposed within said casing and crank case, connecting means between one end of said beam and the piston, means for operating the o positeend of said beam, ing said beam near the center thereof, one end of the said bellows bein hermetically sealed to the surrounding 6. A compressor casing, a cylinder having a piston therein mounted on the casing, a crankcase extending laterally from said cas-.

a walking beam disposed within said casing and crank case, connectin means hetween one end of said beam and t e said piston, means for operating the opposite end of said beam, a bellows surrounding said beam near the center thereof, one end of the said bellows being hermetically sealed to the Suf rounding crank case and the opposite end being similarly sealed to the said walking beam, a member extending outward from the said walking beam where said bellows is sealed thereto, arms extending laterally fromsaid member toward the longitudinal center of said bellows, and bearingsin said arms at the approximate longitudinal center of said bellows and bearing pins extending inward from said casing and engaging said bearings;

7. A compressor-casing, a cylinder having a piston therein mounted on the casing, a crank case extending laterally from said casing. a walking beam disposed within said casing and crank case, connecting means between one end of said beam and the said piston, means for operating the opposite end of said beam, a bellows surrounding said beam near "the center thereof, one end of the said bellows bein hermetically sealed to the surrounding cran case and the opposite end being similarly sealedto the said walking beam,'a member extending outward from the said walking beam where said bellows is sealed thereto,

arms extending laterally from said member ing and the opposite end being similarly sealed to said walking beam, and a fulcrum for said beam at the approximate longitudinal center of the said bellows. 9. A pump adapted for refrigerating systems comprising, a sealed air-tight housing,

a compression chamber in the housing, displacement means'for pum ing gas from the compression chamber; an means for trans mit-ting power through the wall of the hous- 10 wall of thehousing and exten ing inwardly ber extending through the partition for conterns comprismg, a sealed air-tight housing,

from the wall thereof; and a movable memveying movement to said displacement means.

10. A pump adapted for refrigerating sysa compression chamber in the housing, displacement means for pumping gas from the vcompression chamber; andmeans for transmitting power through the wall of the house 20 ing for operating said displacement means,

said power-transmitting means including a non-rotating, flexible tubular partition se cured gas-tight over an opening through the wall of the housing, a, movable member ex-' tending through the partition for conveying movement to'said displacement means, and means for supporting the movable member from the housing comprising a U-shaped arm member rigidly secured to the movable member and having a bearing connection with said housing.

11. A pump adapted for refrigerating sys tems comprising, a sealed air-tight housing having a pump cylinder therein, .a piston and connecting rod guided for reciprocating movement; and means for transmitting power through the wall of thehousing for Operating said piston, said power-transmitting means including a non-rotating, flexible tubular partition secured gas-tight over an opening through the wall of the housingyand a movable member extending through the partition in a direction approximately at right angles to the axisof said p ston and having a slot connection with said piston rod.

12. A power transmitting device for pumps comprising in combination, a wall and means for transmitting power through the wall including a movable power transmitting member and a'partition sealed to the wall and connected to the member, the partition including a ,flexibletubular portion and the parts being so constructed and arranged that during movement/of the member the central axes perpendicular to the end planes ofthe tubular portion intersect substantially midway between the normal positions ofthe ends of the tubular portion.

13. A power transmitting device for pumps comprising in combination, a wall; and means for transmitting power through the wall including a movable power transmitting member and a partition sealedto the wall and connected to the member, the partition including a flexible tubular portion and the parts being so constructed and arranged that for a given flexure of the tubular portion the resistance to such flexure developed by the tubular. portion is a minimum.

14. A power transmitting device for pumps comprising in combination, a wall and means for transmittin pgwer through the wall including a mova Is power transmitting member and a partition sealed to the wall and connected to the member, the partition includin a flexible tubular portion and the parts being so constructed and arranged that during movement of the member the tubular portion partakes of its natural flexing movement. 15. A power transmitting device'for pumps comprising in combination, a wall; and means for transmittin power through the wall in-v 1 cluding a mova le power transmitting mem ber and, a partition sealed to the wall and connected to the member, the partition includin aflexible tubular portion and the parts being so constructed and arranged that for a and the parts being soconstructed and arranged that during movement of the member the central axes perpendicular to the end planes of the tubular portion intersect between the normal positions of the end planes of the tubular portion.

17. A power transmitting device for pumps comprising in combination, a wall; and means for transmitting power through the wall including a movable power transmitting menu her and a partition sealed to the wall and connected to the member, the partition including a flexible corrugated metal bellows connected to the member, the parts being so constructed and arranged that for a given flexure of the bellows the deformation of any corrugation is a minimum.

18. A power transmitting device for pumps comprising in combination, a-wall; and means for transmittin power through the wall in- I cluding a movahle power transmitting member, (and a partition sealed to the wall and connected to the member, the partition including a flexible tubular portion, and the member having an oscillating portion so disposed. that the center, of oscillation is substantially midway between the normal positions of the end. planes of the tubular portion.

19. A power transmitting device for pumps comprising in combination, a wall; and means for transmitting power through the wall including-a movable power transmitting member and a partition sealed to the wall and connected to the member, the partition includ- 1n being so constructed and arranged that during movement of the member a part of the flexible tubular portion oscillates about a center substantially midwa between the normal positions of the end p anes of the tubular portion.

20.v A power transmittlng device for pumps comprising in combination, a wall; and means for transmittin power through the wall in,- eluding a mova le power transmitting member and a partition sealed to the wall and connected to the member, the partition includin a flexible tubular portion and the parts being so constructed and arranged that during the movement of the member the plane of one end of the tubular portion remains tangent to a sphere Whose center is substantially at the center of the normal axis of the tubular portion.

21. In an apparatus of the character described, the combination of a pump having 7 a housing; a driving means; and a sealed driving connection between the driving means and the pump comprising a flexible tubular partition sealed to the housing and a movable member extending from the driving means through the partition for conveying the movement of the driving means to-the pump, said movable member being so mounted as to provide a natural flexing of the partition.

22. In an apparatus of the class described,

the combination of a pum having a housing; drivingrmeans; and a sea ed driving connection between the driving means and the pump comprising a bellows sealed to the housing and a movable member extending from the driving means through the bellows for conveying the movement of the driving means to the, pump, said movable member being mounted to rock about a fixed axis interme: diate the ends of the bellows.

23. In an apparatus of the character described, the combination of a pump; driving means; and a sealed drivin connection between the driving means and the pump comprising a bellows sealed to the housing, a movable member extending from the driving means through the bellows for conveying the movement of the driving means to the pump, and bearing means for'the movable member outside of the bellows so constructed and arranged as to permit natural flexing of the bellows.

In testimony whereof I hereto aflix my sig- 1 nature.

JESSE G. KING.

a flexible tubular portion and the parts 

